已知x,y满足(x-3)^2+(y-3)^2=1.(1)(y-1)/(x-1)范围.(2)y-2x范围.(3)x^2+y^2-2y最大值.

问题描述:

已知x,y满足(x-3)^2+(y-3)^2=1.(1)(y-1)/(x-1)范围.(2)y-2x范围.(3)x^2+y^2-2y最大值.

(x-3)^2+(y-3)^2=1圆心C(3,3),半径r=1(1)令(y-1)/(x-1)=k∴y-1=k(x-1)得到直线l:kx-y+1-k=0∵(x,y)在圆上∴l与圆有公共点∴圆心C到l的距离小于等于半径由点到直线距离公式得d=|3k-3+1-k|/√(k²+1)≤1(2k-2)...